I believe my home state's primary is pivotal. I believe that the mixture of old style Southern Dems as well as our traditional Democratic voters will result in SC's selection of a highly electable Democratic candidate, such as John Edwards last year. SC is a good gauge for how Democratic candidates would do w/ Blue Dog Democrats and moderately liberal Democrats.
But how does that make it "pivotal"? "Pivotal" suggests that it'll have an outsized influence on who wins the nomination, not that it'll vote for the most electable candidate. And with all due respect to SC, aren't there any number of Southern and Western states that have a similar proportion of moderate Dems? Couldn't you make the same case for, say, Oklahoma, which voted on the same day as SC in 2004?